KR20070068295A - Copper foiled substrate - Google Patents

Abstract

A copper-attached plate is provided to secure excellent dimensional stability and heat resistance, to form fine wiring, and to prevent deformation even in using lead-free soldering. The copper-attached plate comprises a polyimide film consisting of paraphenylene diamine of 10~50mol.%, 4,4'-diaminodiphenyl ether of 50~90mol.%, and pyromellitic dianhydride of 100mol.% and a copper sheet formed by applying an adhesive agent on one or both surfaces of the polyimide film. The adhesive agent is not applied on one or both surfaces of the polyimide film, or applied on one surface of the polyimide film and not on the other surface. The polyimide film has elastic modulus of 3~6GPa, a coefficient of linear expansion of 5~20ppm/°C at 50~200°C, a coefficient of humidity expansion below 30ppm/%RH, absorptivity below 3.5%, and heating shrinkage below 0.10% at 200°C for one hour.

Description

Copper attachment plate {COPPER FOILED SUBSTRATE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper-clad board suitable as a material for flexible printed wiring boards, COF, TAB, etc. used in the field of electronic and electrical equipment. It relates to a copper-clad board with a small rate of dimensional change after etching.

Printed wiring boards are widely used in electronic and electrical equipment. Especially, the flexible printed wiring board which can be bent is widely used for the folding part of a personal computer, a mobile phone, etc., and the part which requires the bending of a hard disk. As a material of such a flexible printed wiring board, the board with copper which used various polyimide films is used normally.

Representative examples of the polyimide film used for the copper-clad plate include polyimide films using pyromellitic dianhydride as the acid dianhydride component and 4,4'-diaminodiphenyl ether as the diamine component. Such a polyimide film has a structure excellent in the balance of mechanical and thermal characteristics, and is widely used industrially as a general purpose product. However, the polyimide film made of pyromellitic dianhydride and 4,4'-diaminodiphenyl ether has the advantage of being easy to bend, whereas the substrate is bent when the semiconductor is mounted so that the defect of bonding occurs. there was. In addition, since the polyimide film composed of pyromellitic dianhydride and 4,4'-diaminodiphenyl ether has a high coefficient of thermal expansion (CTE) and a hygroscopic expansion coefficient (CHE) and a high water absorption, dimensions due to heat or absorption When the change was large and fine wiring was formed, there was a problem that the desired wiring width and wiring spacing could not be formed.

In order to solve such a problem, the method of forming a flexible printed wiring board using the base material with small dimension change other than a polyimide film, for example, a liquid crystal film, etc. (for example, refer patent document 1), etc. is disclosed, The liquid crystal film had a problem that heat resistance was inferior compared with a polyimide film, and the base material deform | transformed at the time of soldering. In particular, in recent years, lead-free solders that do not use lead are frequently used due to environmental problems. Since lead-free soldering has a higher melting point than lead-containing solders, the problem of deformation of the substrate of the liquid crystal film is more serious.

Patent Document 1: Japanese Unexamined Patent Publication No. 2005-297405

Accordingly, an object of the present invention is to solve both of the problems of the dimensional change and the heat resistance of the flexible printed wiring board, to form a fine wiring, and to provide a copper-attached plate for a flexible printed wiring board that is not deformed even by using lead-free soldering. It is to offer.

The present invention adopts the following configurations in order to achieve the above object.

 (1) A polyimide film made of paraphenylenediamine, 4,4'-diaminodiphenyl ether, and a pyromellitic dianhydride as an acid dianhydride component is used as a diamine component, and an adhesive agent is used on one side or both sides of this polyimide film. Copper plate attached to having a copper plate through.

 (2) A copper-attached plate having a copper plate without interposing an adhesive on one or both sides of a polyimide film formed of paraphenylenediamine, 4,4'-diaminodiphenyl ether and pyromellitic dianhydride.

 (3) One side of the polyimide film formed of paraphenylenediamine, 4,4'-diaminodiphenyl ether and pyromellitic dianhydride has a copper plate via an adhesive, and the other side has a copper plate without an adhesive. Have copper attachment plate.

 (4) The diamine component of the polyimide film is 10 to 50 mol% of paraphenylenediamine, 50 to 90 mol% of 4,4'-diaminodiphenyl ether, and the acid dianhydride component is 100 mol% of pyromellitic dianhydride ( The plate with copper as described in any one of 1)-(3).

 (5) Elastic modulus 3 to 6 GPa, linear expansion coefficient of 5 to 20 ppm / ℃ at 50 to 200 ℃, humidity expansion coefficient of 30 ppm /% RH or less, absorption rate of 3.5% or less, heat shrinkage rate of 200 ℃ 1 hour The copper adhesion plate in any one of (1)-(4) characterized by using the polyimide film which is 0.10% or less.

 (6) The copper-clad board according to any one of (1) or (3) to (5), wherein the adhesive comprises at least one selected from an epoxy adhesive, an acrylic adhesive and a polyimide adhesive.

 (7) The plate with a copper as described in any one of (1) and (3)-(6) whose surface roughness (Rz) of copper on the adhesion side is 0.1-10 micrometers copper foil.

 (8) The plate with a copper as described in any one of (1)-(7) whose dimension change rate after whole surface etching is in the range of -0.10%-0.10%.

Effects of the Invention

ADVANTAGE OF THE INVENTION According to this invention, the board with a copper which can be used as a material of the flexible printed wiring board which can form fine wiring and does not deform | transform even using lead-free soldering can be provided.

The copper-clad board of this invention uses a polyimide film as a base material, and has a copper plate in the single side | surface or both surfaces of this polyimide film.

At this time, as a polyimide film of the base material, it is a polyimide film which consists of paraphenylenediamine, 4,4'- diamino diphenyl ether as a diamine component, and a pyromellitic dianhydride as an acid dianhydride component. Preferably, 10 to 50 mol% of paraphenylenediamine and 50 to 90 mol% of 4,4'-diaminodiphenyl ether are used as the diamine component, and pyromellitic dianhydride is used as the acid dianhydride component. It is a polyimide film made. More preferably, the modulus of elasticity is 3 to 6 GPa, the coefficient of linear expansion at 50 to 200 ° C is 5 to 20 ppm / ° C, the humidity expansion coefficient is at most 30 ppm /% RH, the absorption is at most 3.5%, at 200 ° C for 1 hour. It is a polyimide film whose heating shrinkage is 0.10% or less. Too much paraphenylene diamine becomes hard and too little to retire, so 10 to 50 mol% is preferred, more preferably 15 to 45 mol%, more preferably 20 to 40 mol%. Too much 4,4'-diaminodiphenylethers recede and too little to harden, so 50 to 90 mol% is preferred, more preferably 55 to 85 mol%, more preferably 60 to 80 mol% to be. The elasticity modulus which is an index of hardness is good in the range of 3-6 GPa, and when it exceeds 6 GPa, it will become hard too much, and when it is smaller than 3 GPa, it will fall back too much. The linear expansion coefficient is preferably 5 to 20 ppm / ° C. If the linear expansion coefficient exceeds 20 ppm / ° C, the dimensional change due to heat is too large. If the linear expansion coefficient is less than 5 ppm / ° C, the difference between the copper plate and the linear expansion coefficient becomes large, so that distortion occurs after etching. If the humidity expansion coefficient exceeds 30 ppm /% RH, the dimensional change due to humidity is too large, so the humidity expansion coefficient is preferably 30 ppm /% RH or less. If the water absorption exceeds 3.5%, the dimensional change of the film is large due to the influence of sucked water, so 3.5% or less is preferable. When the heat shrinkage rate at 200 ° C. for 1 hour exceeds 0.10%, the dimensional change due to heat also becomes large, so the heat shrinkage rate is preferably 0.10% or less.

The polymerization method may be carried out by any known method, for example,

 (1) A method in which the total amount of the aromatic diamine component is first placed in a solvent, and then the aromatic tetracarboxylic acid component is added so as to be equivalent to the amount of the aromatic diamine component and polymerized.

 (2) First, the whole amount of the aromatic tetracarboxylic acid component is put in a solvent, and then, the aromatic diamine component is added so as to be equivalent to the aromatic tetracarboxylic acid component and polymerized.

 (3) After putting one aromatic diamine compound in a solvent and mixing it for the time required for reaction at a ratio which becomes 95-105 mol% of aromatic tetracarboxylic acid compounds with respect to a reaction component, the other aromatic diamine compound is added. And then adding the aromatic tetracarboxylic acid compound to the same amount as the entire aromatic diamine component and the whole aromatic tetracarboxylic acid component so as to polymerize.

 (4) After putting the aromatic tetracarboxylic acid compound in a solvent and mixing for a time required for the reaction at a rate such that one aromatic diamine compound becomes 95 to 105 mol% with respect to the reaction component, an aromatic tetracarboxylic acid compound is added. Then, the other aromatic diamine compound is added and polymerized so that the whole aromatic diamine component and the whole aromatic tetracarboxylic-acid component may be substantially equivalent.

 (5) The polyamic acid solution (A) is adjusted by reacting one of the aromatic diamine components and the aromatic tetracarboxylic acids in excess in the solvent so as to become excess, and the other aromatic diamine component and the aromatic tetracarboxylic acid in the other solvent. The polyamic acid solution (B) is adjusted by reacting the streams so that either side becomes excess. The method of mixing each polyamic-acid solution (A) and (B) obtained in this way, and completing superposition | polymerization. At this time, when adjusting the polyamic acid solution (A), when the aromatic diamine component is excessive, the aromatic tetracarboxylic acid component is excessive in the polyamic acid solution (B), and the aromatic in the polyamic acid solution (A) When the tetracarboxylic acid component is excessive, the polyamic acid solution (B) is made an aromatic diamine component in excess, the polyamic acid solution (A) and (B) are mixed, and the whole aromatic diamine component and aromatics used for these reactions are aromatic. The tetracarboxylic acid component is adjusted to have the same amount.

In addition, the polymerization method is not limited to these, You may use other well-known methods.

In addition, in this invention, as a specific example of the organic solvent used for formation of a polyamic-acid solution, it is dimethyl sulfoxide, for example. Sulfoxide solvents such as diethyl sulfoxide, formamide solvents such as N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide Pyrrolidone solvents, such as an acetamide solvent, N-methyl- 2-pyrrolidone, and N-vinyl- 2-pyrrolidone, phenol, o-, m-, or p-cresol, xylenol, Phenol solvents such as halogenated phenol and catechol, or non-flotone polar solvents such as hexamethylphosphoramide and γ -butyrolactone. The use of aromatic hydrocarbons such as these is also possible.

The polyamic acid solution thus obtained contains 5 to 40% by weight of solid content, preferably 10 to 30% by weight, and the viscosity is 10 to 2000 Pa.s, measured by Brookfield clay meter. Specifically, 100 to 1000 Pa · s is preferably used for stable liquid feeding. In addition, the polyamic acid in the organic solvent solution may be partially imidized.

Next, the manufacturing method of the polyimide film of this invention is demonstrated.

As a method of forming a polyimide film, a method of obtaining a polyimide film by casting a polyamic acid solution into a film form and thermally decyclizing and desolventing therein, and chemically decyclizing by mixing a cyclization catalyst and a dehydrating agent with the polyamic acid solution The method of obtaining a polyimide film by creating a gel film by heating and desolventing it, but the thermal expansion coefficient of the polyimide film obtained by the latter method can be suppressed low.

Moreover, you may add each crystal filler, such as a silica and an alumina, in order to improve the slipperiness | lubricacy of a film. As a particle diameter of these fillers, it is good to use an average particle diameter of 0.1-1 micrometer. If the average particle diameter is less than 0.1 µm, the slipperiness of the film is poor, and if the average particle diameter is more than 1 µm, many aggregates are present during film production, which is not preferable. In addition, when a filler having an average particle diameter of more than 1 µm is used, projections of 20 µm or more in size are more than 10/5 cm × 5 cm on the film surface, and 3/5 cm × 5 convex portions having a height of 2 µm or more. more than cm. The amount of projections of this size is not preferable because the fillers are interposed between the wirings, resulting in poor electrical conductivity, and the problem of puncturing the film thickness of the photoresist mask.

As copper foil used for the copper plate which has an adhesive agent through a copper adhesion plate, it is good that it is copper foil whose surface roughness Rz of copper on the adhesion side is 0.1-10 micrometers. On the other hand, when the surface roughness is used as a sparse surface flexible printed wiring board in the high frequency signal region, the current is less likely to flow due to the surface effect, making it difficult to use in the high frequency region. Surface roughness Rz here is Rz prescribed | regulated to 5.1 "Definition of 10-point average roughness" of JISB O601-1994 "Definition and display of surface roughness".

Although it does not specifically limit about the thickness of a polyimide film, Preferably it is 5-125 micrometers. More preferably 9 to 75 μm, more preferably 11 to 55 μm. If it is too thick, a problem of unwinding when the roll is formed easily occurs, and if too thin, wrinkles are likely to occur.

An adhesive is interposed on one side or both sides of the polyimide film as described above, or a copper plate is formed without the adhesive. When using an adhesive agent, at least 1 sort (s) chosen from an epoxy adhesive, an acrylic adhesive, and a polyimide adhesive is preferable. These adhesives may be provided with various rubbers, plasticizers, hardeners, flame retardants such as phosphorus, and other various additives. In addition, although thermoplastic polyimide is used mainly as a resin component of a polyimide-type adhesive agent, a thermosetting polyimide may be sufficient. In addition, as a polyimide adhesive, you may use a thermoplastic polyimide film as an adhesive agent.

The dimensional change rate after the front etching of the copper-clad board is in the range of -0.10% to 0.10%, and more preferably in the range of -0.O5% to 0.O5% so that the problem of mounting as a flexible printed wiring board does not appear. I like it, and more preferably, it is -0.O3%-0.O3%.

Example

Hereinafter, an Example is given and it demonstrates concretely. In addition, although the polyimide film used by an Example uses what was formed into a film by the method of the synthesis examples 1-6, it is not limited to these. In addition, the polyimide film used by the comparative examples 1-2 uses the film formed by the synthesis examples 7-8. In addition, although the agent prepared by the synthesis examples 9-10 is used as an adhesive agent used in an Example, it is not limited to these.

In addition, each characteristic of the polyimide film obtained by the synthesis example, and the copper plate of an Example was evaluated by the following method.

 (1) film thickness

It was measured as follows using a Lightmatictic (Series 318) thickness meter manufactured by Mitutoyo. That is, 15 parts were arbitrarily selected from the film front surface, the thickness about this 15 part was measured, the average was computed, and it was set as thickness.

 (2) linear expansion coefficient

It measured on the conditions of the measurement temperature range: 50-200 degreeC, and a temperature increase rate: 10 degree-C / min using the TMA-50 thermomechanical analyzer which is a Shimadtsu Seisakusho product. The load was 0.25 N, first, the temperature was raised from 35 ° C to 10 ° C / min, and the temperature was raised to 300 ° C. It hold | maintained at 300 degreeC for 5 minutes, after that, it temperature-falled to 10 degree-C / min, it lowered to 35 degreeC, it hold | maintained at 35 degreeC for 30 minutes, after that, it heated up at 10 degree-C / min and raised temperature to 300 degreeC. The data at the time of temperature rising from 35 degreeC to 300 degreeC of the 2nd was read, and the linear expansion coefficient was computed from the average of 50-200 degreeC parts.

 (3) elastic modulus

Tensile rate using the RTM-250 Tensileron Universal Testing Machine from Aend Disa

Measured under the condition of 100 mm / min. Load cell 10 Kgf, measurement accuracy ± 0.5% Full scale, measure the stress-strain curve, and the slope of the straight line of the rising part of the stress-strain curve (calculated by the least square method between 2N and 15N) From the initial sample length, sample width, and sample thickness, it was calculated as follows.

Modulus of elasticity = (Slope X initial sample length) / (sample width X sample thickness)

 (4) humidity expansion coefficient

After installing the film in TM7000 furnace made by ULVAC at 25 ° C, blowing dry air into the furnace and drying it for 2 hours, the inside of the TM7000 furnace was cooled by air from the HC-1 type steam generator. It was humidified with% RH and the humidity expansion coefficient was obtained from the dimensional change therebetween. Humidification time was 7 hours. Data from 3% RH to 90% RH was read, and the humidity expansion coefficient was calculated from the average of the portions of 3 to 90% RH.

 (5) water absorption

It was left to stand in a dessicator for 2 days in 98% RH atmosphere, and it evaluated by the weight percent increase with respect to the weight at the time of drying.

 (6) heating shrinkage

A film of 20 cm × 20 cm was prepared, and the film dimension (L1) after standing for 2 days in a room adjusted to 25 ° C. and 60% RH was measured, and subsequently heated to 200 ° C. for 60 minutes, and then again 25 ° C. and 60 ° C. After leaving in a room adjusted to% RH for 2 days, the film dimension (L2) was measured and evaluated by the following formula calculation.

Heat Shrinkage =-[(L2-L1) / L1] × 100

(7) dimensional change rate

Measurement of the dimensional change rate before and after copper plate etching is performed using a CNC image processing measuring system (NEXIV VMR-3020, manufactured by Nikon Corporation) under conditions of a temperature of 25 ° C. and a humidity of 60%, and a field of view: 1.165 mm × 0.875 mm ( 4 times) was carried out by measuring and calculating the distance between the centers of the circles of the 6 mm circular masking tapes attached to the surface of the copper-clad plate at 210 mm intervals in the MD direction before and after copper front etching. The distance before etching is L3, and the distance after etching is L4, and before and after copper etching, a sample is left overnight under the conditions of temperature 25 degreeC and humidity 60%, and the influence by the absorption of a polyimide is excluded. The dimensional change rate was calculated by the following formula using the average value of the values measured five times between two points.

Dimensional rate of change (%) = [(L3-L4) / L3] × 100 (Synthesis example 1)

Synthesis Example 1

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/75/25, and DMAc (N , N-dimethylacetamide) as a 18.5% by weight solution to obtain a polyamic acid. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, to obtain a gel film having 55 wt% of the remaining volatile components and a self supporting property of about 0.20 mm in thickness. This gel film was peeled from the drum, the both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of 25 micrometers in thickness was obtained.

 Synthesis Example 2

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/75/25, and DMAc (N , N-dimethylacetamide) as a 18.5% by weight solution to polymerize to obtain a polyamic acid. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, and a gel film having 55% by weight of the remaining volatile components and a thickness of about 0.07 mm in thickness was obtained. This gel film was peeled from the drum, and both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of 9 micrometers in thickness was obtained.

 Synthesis Example 3

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/70/30, and DMF (N , N-dimethylformamide) to a 18.5 wt% solution to obtain a polyamic acid. At this time, first, pyromellitic dianhydride and paraphenylenediamine were first reacted, and then block polymerization was performed in which 4,4'-diaminodiphenyl ether was added. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, and a gel film having 55% by weight of the remaining volatile components and a thickness of about 0.10 mm was obtained. This gel film was peeled from the drum, the both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of thickness 12.5micrometer was obtained.

 Synthesis Example 4

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/80/20, and DMAc (N , N-dimethylacetamide) as a 18.5% by weight solution to polymerize to obtain a polyamic acid. At this time, first, the pyromellitic dianhydride and 4,4'-diaminodiphenyl ether were first reacted, and then block polymerization was performed in which paraphenylenediamine was added. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amide acid group of the polyamic acid. The obtained mixture was cast on an endless belt from a T-type slit die and heated by hot air at 70 ° C. to obtain a gel film having 55 wt% of the remaining volatile components and a self supporting property of about 0.05 mm in thickness. This gel film was peeled from the drum, and both ends were gripped, and 200 degreeC * 60 second, 350 degreeC * 60 second, and 550 degreeC * 45 second process was performed by the heating furnace, and the polyimide film of thickness 6micrometer was obtained.

 Synthesis Example 5

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/50/50, and DMF (N , N-dimethylformamide) to a 18.5 wt% solution to obtain a polyamic acid. At this time, first, pyromellitic dianhydride and paraphenylenediamine were first reacted, and then block polymerization was performed in which 4,4'-diaminodiphenyl ether was added. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, to obtain a gel film having 55% by weight of the remaining volatile components and about 1.0 mm in thickness. This gel film was peeled from the drum, the both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the 125-micrometer-thick polyimide film was obtained.

 Synthesis Example 6

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenylether (molecular weight 200.24) / paraphenylenediamine (molecular weight 108.14) was mixed in a molar ratio at a ratio of 100/60/40, and DMAc (N , N-dimethylacetamide) as a 18.5% by weight solution to polymerize to obtain a polyamide acid. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, to obtain a gel film having 55% by weight of the remaining volatile components and a thickness of about 0.40 mm. This gel film was peeled from the drum, and both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of 50 micrometers in thickness was obtained.

 Synthesis Example 7

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenyl ether (molecular weight 200.24) was mixed at a molar ratio of 50/50 in a ratio of 18.5% by weight of DMF (N, N-dimethylformamide) It superposed | polymerized as and obtained polyamic acid. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, to obtain a gel film having 55 wt% of the remaining volatile components and a self supporting property of about 0.20 mm in thickness. This gel film was peeled from the drum, the both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of 25 micrometers in thickness was obtained.

 Synthesis Example 8

Pyromellitic dianhydride (molecular weight 218.12) / 4,4'-diaminodiphenyl ether (molecular weight 200.24) was mixed at a molar ratio of 50/50 in a ratio of 18.5% by weight of DMF (N, N-dimethylformamide) It superposed | polymerized as and obtained polyamic acid. A conversion agent consisting of acetic anhydride (molecular weight 102.09) and isoquinoline was mixed and stirred at a ratio of 50% by weight based on the polyamic acid solution. At this time, acetic anhydride and isoquinoline were prepared so as to be 2.0 and 0.4 molar equivalents, respectively, with respect to the amic acid group of the polyamic acid. The obtained mixture was cast on a stainless steel drum rotated from a T-type slit die on a stainless steel drum, to obtain a gel film having 55% by weight of the remaining volatile components and a thickness of about 0.10 mm. This gel film was peeled from the drum, and both ends were gripped, and 200 degreeC * 30 second, 350 degreeC * 30 second, and 550 degreeC * 30 second process was performed by the heating furnace, and the polyimide film of 12.5 micrometers in thickness was obtained.

The characteristic of the synthesis examples 1-8 is put together in Table 1, and is shown.

PMDA 4,4'-ODA PPD Thickness (㎛) Coefficient of linear expansion (ppm / ℃) Modulus of elasticity (GPa) Humidity Expansion Coefficient (ppm /% RH) Absorption rate (%) Heating shrinkage (%) Synthesis Example 1 100 75 25 25 17.3 4.2 19.3 2.7 0.05 Synthesis Example 2 100 75 25 9 17.5 4.2 19.0 2.7 0.05 Synthesis Example 3 100 70 30 12.5 15.4 4.4 20.0 2.8 0.07 Synthesis Example 4 100 80 20 6 19.5 4.0 17.3 2.7 0.05 Synthesis Example 5 100 50 50 125 9.2 5.2 23.6 3.4 0.08 Synthesis Example 6 100 60 40 50 12.0 4.9 22.5 3.2 0.05 Synthesis Example 7 100 100 0 25 25.0 3.5 24.0 2.9 0.25 Synthesis Example 8 100 100 0 12.5 27.0 3.5 24.0 2.9 0.25

PMDA in the table is pyromellitic dianhydride,

    4,4'-ODA is 4,4'-diaminodiphenyl ether,

    PPD is paraphenylenediamine.

 Synthesis Example 9

6 parts by weight of epoxy resin `` Epicoat '' from Yuka Shell Co., Ltd., 100 parts by weight of phosphorus-containing epoxy resin FX279BEK75 from Todogasei Co., Ltd., and 4,4'-DDS curing agent from Sumitomogagaku Co. Parts by weight, 100 parts by weight of NBR (PNR-1H) manufactured by JSR Corporation, and 30 parts by weight of aluminum hydroxide, produced by Showa Denko, were stirred and mixed with 600 parts of methyl isobutyl ketone at 30 ° C to obtain an adhesive solution. .

 Synthesis Example 10

50 parts by weight of Yuka Shell Co., Ltd. epoxy coat `` Epicoat '' 828, 80 parts of Todo Kasei Co., Ltd. phosphorus epoxy resin FX279BEK75, and 6,4'-DDS curing agent from Sumitomogagaku Co., Ltd. 100 parts by weight of NBR (PNR-1H) manufactured by JSR Co., Ltd., and 10 parts by weight of aluminum hydroxide, manufactured by Showa Denko Co., Ltd., were stirred and mixed at 600 ° C in methyl isobutyl ketone at 30 ° C. Got it.

 (Example 1)

Using the polyimide film formed into the film by the synthesis example 1, the adhesive agent of the synthesis example 9 was apply | coated to this single side | surface, it heat-dried at 150 degreeC x 5 minutes, and formed the adhesive layer of 10 micrometers of dry film thicknesses. This single-sided polyimide film with adhesive and 1/2 ounce copper foil (FO-WS18, manufactured by Furukawa Circuit Foil Co., Ltd.) having a surface roughness (Rz) of 1.5 µm were laminated using a heat roll laminate machine to a laminate temperature of 160 ° C. The thermal lamination was performed on the conditions of the pressure of 196 N / cm (20 kgf / cm <2>), and the lamination speed | rate 1.5 m / min, and the single-sided flexible copper plate was produced. Using the obtained copper-clad board, the rate of dimensional change before and after copper full surface etching was measured, and the rate of dimensional change was -0.004%.

 (Example 2)

Except using the polyimide film formed into the film by the synthesis example 2, it carried out similarly to Example 1, and produced the single-sided copper plate. The dimensional change rate before and after copper front surface etching was measured and found to be -0.006%.

 (Example 3)

Except using the polyimide film formed into the film by the synthesis example 3, it carried out similarly to Example 1, and produced the single-sided copper plate. The dimensional change rate before and after copper front surface etching was measured, and the dimensional change rate was 0.015%.

 (Example 4)

Except using the polyimide film formed into the film by the synthesis example 4, it carried out similarly to Example 1, and produced the single-sided copper plate. The dimensional change rate before and after copper front surface etching was measured, and the dimensional change rate was -0.021%.

 (Example 5)

After using the polyimide film formed in the synthesis example 2, the vacuum chamber was made into 1 x 10 <^-3> Pa of pressure, and nickel / chromium = 95/5 (weight ratio) by DC magnetron spatter at argon gas pressure of 1 x 10 <^-1> Pa. Nichrome alloy was sputtered on one side to have a thickness of 5 nm, and copper was sputtered to have a thickness of 50 nm. Next, the 6-micrometer-thick copper layer was laminated | stacked on the conditions of the current density of 2 A / dm <^2> by the electroplating by the copper sulfate bath, and the single-sided copper plate was produced. As the composition of the copper sulfate bath, a solution in which an appropriate amount of an additive was added to 80 g / liter of copper sulfate pentahydrate, 200 g / liter of sulfuric acid, and 50 mg / liter of hydrochloric acid was used. When the obtained copper clad board was used, the dimensional change rate in the front and back of copper front etching was measured, and the dimensional change rate was 0.012%.

 (Example 6)

Using the polyimide film formed into a film by the synthesis example 5, the adhesive agent of the synthesis example 10 was apply | coated to this single side | surface, it heat-dried at 150 degreeC x 5 minutes, and formed the adhesive layer of 10 micrometers of dry film thicknesses. This single-sided adhesive polyimide film and 1/2 ounce copper foil (FO-WS18, manufactured by Furukawa Circuit Foil Co., Ltd.) having a surface roughness (Rz) of 1.5 µm were laminated using a heat roll laminate machine, and the lamination temperature was 160 ° C. The thermal lamination was performed on the conditions of the pressure of 196 N / cm (20 kgf / cm <2>), and the lamination speed | rate 1.5 m / min, and the plate with a single-sided copper was produced. When the obtained copper clad board was used, the dimension change rate before and behind copper front surface etching was measured, and the dimension change rate was 0.014%.

 (Example 7)

After using the polyimide film formed in the synthesis example 4, the vacuum chamber was made into 1 x 10 <^-3> Pa of pressure, and nickel / chromium = 90/10 by DC magnetron spatter at argon gas pressure of 1 x 10 <^-1> Pa (weight ratio) Nichrome alloy was sputtered on one side to have a thickness of 3 nm, and copper was sputtered to have a thickness of 10 nm. Next, the copper layer of 5 micrometers thickness was laminated | stacked on the conditions of the current density of 2 A / dm <^2> by the electroplating by a copper sulfate bath, and the single-sided copper clad plate was produced. As the composition of the copper sulfate bath, a solution in which an appropriate amount of an additive was added to 80 g / liter of copper sulfate pentahydrate, 200 g / liter of sulfuric acid, and 50 mg / liter of hydrochloric acid was used. Using the obtained copper-clad board, the dimensional change rate before and after the copper front etching was measured, and the dimensional change rate was 0.008%.

 (Example 8)

After using the polyimide film formed in the synthesis example 6, the vacuum chamber was made into the reaching pressure of 1x10 <^-3> Pa, and nickel / chromium = 90/10 by DC magnetron spatter at argon gas pressure of 1x10 <^-1> Pa (weight ratio Nichrome alloy was sputtered on one side to have a thickness of 3 nm, and copper was sputtered to have a thickness of 10 nm. Next, the copper layer of 12 micrometers thickness was laminated | stacked on the conditions of the current density of 2 A / dm <^2> by the electroplating by a copper sulfate bath, and the single-sided copper plate was produced. As the composition of the copper sulfate bath, a solution in which an appropriate amount of an additive was added to 80 g / liter of copper sulfate pentahydrate, 200 g / liter of sulfuric acid, and 50 mg / liter of hydrochloric acid was used. Using the obtained single-sided copper-clad board, the adhesive of Synthesis Example 8 was applied to the opposite side (polyimide surface) of the surface on which the copper layer was formed, heated and dried at 150 ° C. for 5 minutes, and an adhesive layer having a dry film thickness of 10 μm. Formed. Single-sided copper-clad board with adhesive and 1/3 ounce copper foil (Rz) of 1.5 µm (FO-WS12, manufactured by Furukawa Circuit Foil Co., Ltd.) using a heat roll laminate machine, laminate temperature 160 ° C, laminate pressure 196 N thermal lamination under the conditions of / cm (20 kgf / cm 2) and a lamination speed of 1.5 m / min, one side is via an adhesive, and the other side is a double-sided copper plate attached with copper without an adhesive. Got it. Using the obtained double-sided copper plate, the rate of dimensional change before and after the entire copper etching was measured, and the rate of dimensional change was 0.011%.

 (Comparative Example 1)

Except using the polyimide film formed into the film by the synthesis example 7, it carried out similarly to Example 1, and produced the single-sided copper plate. The dimensional change rate before and after the copper front etching was measured, and the dimensional change rate was -0.122%.

 (Comparative Example 2)

Except using the polyimide film formed into the film by the synthesis example 8, it carried out similarly to Example 1, and produced the single-sided copper plate. The dimensional change rate before and after copper front surface etching was measured and found to be -0.132%.

 (Comparative Example 3)

Except for using the polyimide film formed into a film by the synthesis example 7, it carried out similarly to Example 1, and produced the board with a double-sided copper. The dimensional change rate before and after the copper front surface etching was measured and found to be -0.105%.

The dimensional change rate of Examples 1-8 and Comparative Examples 1-3 was put together in Table 2, and is shown.

Dimensional rate of change (%) Example 1 -0.004 Example 2 -0.006 Example 3  0.015 Example 4 -0.021 Example 5  0.012 Example 6  0.014 Example 7  0.008 Example 8  0.004 Comparative Example 1 -0.122 Comparative Example 2 -0.132 Comparative Example 3 -0.105

According to the present invention, it is possible to provide a copper steel sheet which is very suitable for flexible wiring boards having excellent dimensional stability and heat resistance.

Claims (8)

Copper attachment plate which has a copper plate using the polyimide film formed from paraphenylenediamine, 4,4'- diamino diphenyl ether, and a pyromellitic dianhydride, and an adhesive on one side or both sides of this polyimide film. . A copper adhesion plate having a copper plate without interposing an adhesive on one or both sides of a polyimide film formed of paraphenylenediamine, 4,4'-diaminodiphenyl ether and pyromellitic dianhydride.  One side of the polyimide film formed of paraphenylenediamine, 4,4'-diaminodiphenylether and pyromellitic dianhydride has a copper plate via an adhesive, and the other side has a copper plate without an adhesive. Attachment plate. The diamine component according to any one of claims 1 to 3, wherein the diamine component is 10 to 50 mol% of paraphenylenediamine, 50 to 90 mol% of 4,4'-diaminodiphenyl ether, and an acid dianhydride. The copper adhesion plate whose component is 100 mol% of pyromellitic dianhydride. The water absorption rate according to any one of claims 1 to 4, wherein the linear expansion coefficient at an elastic modulus of 3 to 6 GPa, 50 to 200 ° C is 5 to 20 ppm / ° C, and the humidity expansion coefficient is 30 ppm /% RH or less. The 3.5% or less of this, and the polyimide film whose heat shrinkage rate of 200 degreeC 1 hour is 0.10% or less is used. The copper attachment plate according to any one of claims 1 to 3, wherein the adhesive comprises at least one selected from an epoxy adhesive, an acrylic adhesive, and a polyimide adhesive. The copper adhesion plate in any one of Claim 1 or 3-6 whose surface roughness Rz of copper on the adhesion side is a copper foil of 0.1-10 micrometers. The copper clad plate according to any one of claims 1 to 7, wherein the rate of dimensional change after the entire surface etching is in the range of -0.10% to 0.10%.